______,Keep warm in a 250° oven.,Melt margarine in a 2-quart saucepan.,Stir in the brown sugar, corn syrup and salt.,Bring to a rolling boil, stirring constantly.,Boil without stirring for 5 minutes.,Stir in baking soda and vanilla.,Quickly pour over warm popped corn and peanuts mixture while tossing until popped corn and nuts are well coated.,Bake at 250° for 45 minutes.,Stir every 15 minutes.,Make sure every piece of popcorn has been moved.,Turn out on aluminum foil.,Store in a tight container.